Durability of thermally modified sapwood and heartwood of Scots pine and Norway spruce in the modified double layer test

In the present study, durability of untreated and thermally modified sapwood and heartwood of Scots pine and Norway spruce was examined using a modified double layer test. Base layer samples were partly on contact with ground where exposure conditions were harder than that in a double layer test above the ground. The base layer on ground contact gave results already after one year of exposure in Finnish climate, but the top layer of a double layer test element simulated more the situation of decking exposure.

Significant differences in durability and moisture content (MC) between the wood materials were detected after six years of exposure in the field. Thermally modified pine heartwood performed very well in all layers of the test element and only minor signs of decay were found in some of the base samples. Both sapwood and heartwood of thermally modified spruce were suffering only slight amounts of decay while thermally modified pine sapwood was slightly or moderately decayed. Untreated sapwood samples of pine and spruce were severely decayed or reached failure rating after six years in the field. Untreated heartwood samples performed clearly better. The highest MCs were measured from untreated and thermally modified pine samples. Thermal modification increased significantly the durability and decreased the MC values of all wood materials.     

Edge effects and trampling in boreal urban forest fragments – impacts on the soil microbial community

Fragmentation of forest ecosystems increases the proportion of edge habitat and is accompanied by a change in plant species composition. The recreational use of urban forests leads to decreased vegetation cover and the formation of paths, and thus, to fragmentation at small scales. We studied the impacts of forest and path edge effects on the soil microbial community structure (by using the phospholipid fatty acid (PLFA) method) and microbial activity (measured as basal respiration) in 34 mesic boreal urban forest fragments in Finland. We sampled the humus layer 1) from the forest edge into the interior (0–80 m), and 2) at different distances from paths. Microbial community structure was only slightly affected by the forest edge but differences were found between distances of 0–10 m and over 50 m from the edge. These changes correlated with changes in soil pH. Although changes in the microbial community structure were not pronounced, microbial biomass and activity were 30–45% lower at the first 20 m into the forest fragments, due to a low moisture content of the humus near the edge. The decreased microbial activity detected at forest edges implies decreased litter decomposition rates, and thus, a change in ecosystem nutrient cycling. The microbial community structure differed between paths and surrounding areas and correlated with changes in soil pH. Paths also supported approximately 25–30% higher microbial biomass with a transition zone of at least 1 m from the path edge. Path associated disturbances (mainly alterations in vegetation and soil pH) were reflected in the soil microbial community structure up to 1.5 m from the paths.     

Sexual Reproduction of European Aspen (Populus tremula L.) at Prescribed Burned Site: The Effects of Moisture Conditions

Aspen (Populus tremula) is capable of reproducing both sexually and asexually from root suckers, the latter being more common. Seedlings are rare even though potential seed production is enormous. The aim of this study was to find out how different moisture conditions affect emergence and survival of aspen seedlings on burned soil. We set up a sowing experiment on mineral soil and on humus. The sowing was done at 240 microsites (θ7 cm) in 15 blocks (1×1 m). Treatments were sowing time, watering and sowing shelter. A total of 1463 seedlings emerged on mineral soil and 26 on humus. Watering, covering, their interaction, block and sowing time had significant effects on the number of seedlings. The largest numbers of seedlings were recorded at microsites that were watered and covered. The survival of seedlings was 20% during the growing season and 45% over winter. We conclude that seedbed conditions and moisture are the most essential factors for sexual reproduction of aspen. Short-term weather conditions have an important effect on seedling emergence and are likely to greatly affect field studies.     

Association of bovine respiratory disease with clinical status and acute phase proteins in calves

Eighty-four calves with respiratory disease from 18 herds in different parts of Finland were chosen for a study evaluating the capacity of different respiratory pathogens to cause changes in different acute phase protein concentrations, white blood cell (WBC) count and clinical signs. The selected acute phase proteins were fibrinogen, haptoglobin, serum amyloid-A, lipopolysaccharide binding protein and alpha1-acid glycoprotein. From each calf, a paired blood sample was obtained for serological studies of bovine parainfluenza virus-3, bovine respiratory syncytial virus, bovine coronavirus, bovine adenovirus-3 and bovine adenovirus-7. Tracheobronchial lavage was performed to detect bacteria and mycoplasma. Isolation of Pasteurella multocida was associated with increased concentrations of all tested acute phase proteins. For other pathogens, no significant relationships were observed. No association was present between viral or bacterial findings and WBC count.     

Dendroclimatological analysis of seeded and thinned Scots pine (<Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.) stands at the coniferous timberline

Radial growth was examined in two Scots pine stands that were seeded during the 1920s and 1930s due to reforestation and afforestation activity on the timberline of northern Finnish Lapland. Tree-rings of seeded pines were calibrated against the instrumental records of local weather and large-scale atmospheric patterns and further compared to pines of natural origin on the timberline. The studied stands were shown to contain common growth variability that differed from the variability of natural pines. Deviating growth of seeded pines was attributed to their only moderate growth dependence on mid-summer (July) temperatures and, likewise, their strong dependence on the autumn climate in the previous year, and linked to the different genetic origin of artificial stands due to southern seeds. Stands were thinned for different densities in 1985 and 1986. The growth response to thinning was markedly better than could be expected according to previous studies. We found that the positive growth reaction conceivably benefited from the ameliorated winter conditions, expressed as warmed (March) temperatures and the prolonged positive phase of the Arctic Oscillation (February). The results emphasize the determining influence of climatic fluctuations on reforestation and afforestation near the distributional limits of tree species.     

Treefall gaps of certified,conventionally managed and natural forests as regeneration sites for Neotropical timber trees in northern Honduras

Forest certification programmes promote sustainable management of the world's forests. Certification can be given to a forest management system that fulfils certain environmental, social and economic criteria.     

Inhibition of Angiotensin converting enzyme I caused by autolysis of potato proteins by enzymatic activities confined to different parts of the potato tuber

Autolysis of protein isolates from vascular bundle and inner tuber tissues of potato (Solanum tuberosum) enhanced the inhibition of the angiotensin converting enzyme I (ACE), a biochemical factor affecting blood pressure (hypertension). The physiological age of the tuber affected the strength of ACE inhibition, the rate of its increase during autolysis, and the tuber tissue where ACE inhibition was most pronounced. The highest inhibitory activities (50% reduction in ACE activity achieved following autolysis at a protein concentration of 0.36 mg mL (-1)) were measured in tubers after 5-6 months of storage prior to sprouting. The rate of ACE inhibition was positively correlated with protease activity in tuber tissues. Amendment of the autolysis reaction with protein substrates from which bioactive ACE-inhibitory peptides may be released, for example, a purified recombinant protein or a concentrate of total tuber proteins, also enhanced ACE inhibition. Many tuber proteins including aspartic protease inhibitors were degraded during autolysis. The data provide indications of differences in the enzymatic activities confined to different parts of the potato tuber at different physiological stages. Results suggest that native enzymes and substrate proteins of potato tubers can be utilized in search of dietary tools to manage elevated blood pressure.     

Ice fishing reveals size structure but not abundance of Eurasian perch in small boreal lakes

Management of inland recreational fisheries would benefit from stock abundance and size structure data. Feasibly standardised angling methods such as ice fishing could produce representative catch-per-unit-effort (CPUE) information on the abundance of different-sized fish in small lakes. Here, we first used standard Nordic multimesh gillnets to obtain number-per-unit-effort (NPUE), biomass-per-unit-effort (BPUE) and size structure data on Eurasian perch (Perca fluviatilis) stocks in 11 small boreal lakes in summer. Second, the same lakes were ice-fished by voluntary anglers using a pre-defined, loosely standardised protocol to obtain angling-based NPUE, BPUE, and length frequency distributions. Effects of environmental variables such as water oxygen concentration and light penetration on angling catch rates were controlled statistically. Neither perch Nordic gillnet NPUE nor BPUE corresponded to ice-fishing CPUEs. However, the length distribution of the catch did not differ between methods. Our results imply that traditional ice fishing applying natural baits is relatively unselective for fish size and could produce valid length-based indicators for management purposes while angling CPUE was poorly related to Nordic gillnet CPUE.     

Degradation of Secalins During Rye Sourdough Fermentation

Rye sourdough (RSD) gives rye bread mildly acidic taste and desired flavor. Flavor precursors (amino acids and small peptides) are generated in the proteolytic breakdown of rye proteins. Our aim was to study the protein degradation during RSD fermentations. Two sourdoughs were prepared of flours derived from two rye cultivars (Amilo and Akusti). RSD samples were collected during fermentations. Three protein fractions were obtained by sequential protein extraction and these were analyzed by SDS‐PAGE. Free amino nitrogen (FAN) was measured with a ninhydrin method. In addition, two rye incubations without starter microorganisms (with antibiotics) were made at pH 3.6 and 6.1, and proteinase profiles of the rye cultivars were analyzed at pH 4.3. SDS‐PAGE analysis showed that during RSD fermentations, rye proteins, especially the alcohol‐soluble secalins, were degraded. Secalins also evidently degraded during the incubation without starter microorganisms at pH 3.6. Aspartic proteinases were in the major proteinase group in both rye cultivars. This study confirms that endogenous proteinases of rye, mainly aspartic proteinases, hydrolyze rye proteins, especially secalins, during RSD fermentation. Protein degradation in rye sourdoughs may thus be enhanced by selecting rye flours with high proteolytic activity toward secalins.     

Berry phenolic extracts modulate the expression of p21(WAF1) and Bax but not Bcl-2 in HT-29 colon cancer cells

Previous studies have shown that anthocyanin-rich berry extracts inhibit the growth of cancer cells in vitro. The objective of this study was to compare the effects of berry extracts containing different phenolic profiles on cell viability and expression of markers of cell proliferation and apoptosis in human colon cancer HT-29 cells. Berry extracts were prepared with methanol extraction, and contents of the main phenolic compounds were analyzed using HPLC. Anthocyanins were the predominant phenolic compounds in bilberry, black currant, and lingonberry extracts and ellagitannins in cloudberry extract, whereas both were present in raspberry and strawberry extracts. Cells were exposed to 0-60 mg/mL of extracts, and the cell growth inhibition was determined after 24 h. The degree of cell growth inhibition was as follows: bilberry > black currant > cloudberry > lingonberry > raspberry > strawberry. A 14-fold increase in the expression of p21WAF1, an inhibitor of cell proliferation and a member of the cyclin kinase inhibitors, was seen in cells exposed to cloudberry extract compared to other berry treatments (2.7-7-fold increase). The pro-apoptosis marker, Bax, was increased 1.3-fold only in cloudberry- and bilberry-treated cells, whereas the pro-survival marker, Bcl-2, was detected only in control cells. The results demonstrate that berry extracts inhibit cancer cell proliferation mainly via the p21WAF1 pathway. Cloudberry, despite its very low anthocyanin content, was a potent inhibitor of cell proliferation. Therefore, it is concluded that, in addition to anthocyanins, also other phenolic or nonphenolic phytochemicals are responsible for the antiproliferative activity of berries.